Pinyin4j is a Java library that converts Chinese characters to their corresponding Pinyin (phonetic) representation. It supports multiple Pinyin systems and provides various output formats, making it a versatile tool for Chinese language processing in Java applications.

Pros

• Supports multiple Pinyin systems (Hanyu Pinyin, Tongyong Pinyin, Wade-Giles, etc.)
• Offers various output formats (with or without tone marks, with tone numbers, etc.)
• Handles both Simplified and Traditional Chinese characters
• Lightweight and easy to integrate into Java projects

Cons

• Limited to Java applications, not available for other programming languages
• May not handle some rare or complex Chinese characters accurately
• Lacks built-in support for sentence-level tone sandhi rules
• Documentation could be more comprehensive and up-to-date

Code Examples

1. Basic Pinyin conversion:

PinyinHelper.toHanyuPinyinStringArray('中');
// Output: ["zhong1"]

2. Converting a string to Pinyin with tone marks:

HanyuPinyinOutputFormat format = new HanyuPinyinOutputFormat();
format.setToneType(HanyuPinyinToneType.WITH_TONE_MARK);
format.setVCharType(HanyuPinyinVCharType.WITH_V);

String pinyin = PinyinHelper.toHanyuPinyinString("你好世界", format, " ");
// Output: "nǐ hǎo shì jiè"

3. Getting multiple Pinyin representations:

String[] pinyinArray = PinyinHelper.toHanyuPinyinStringArray('重');
// Output: ["zhong4", "chong2"]

Getting Started

1. Add the Pinyin4j dependency to your project:

   For Maven:

   <dependency>
       <groupId>com.belerweb</groupId>
       <artifactId>pinyin4j</artifactId>
       <version>2.5.1</version>
   </dependency>
   

   For Gradle:

   implementation 'com.belerweb:pinyin4j:2.5.1'
   

2. Use the library in your Java code:

   import net.sourceforge.pinyin4j.PinyinHelper;
   import net.sourceforge.pinyin4j.format.HanyuPinyinOutputFormat;
   import net.sourceforge.pinyin4j.format.HanyuPinyinToneType;
   
   public class PinyinExample {
       public static void main(String[] args) {
           String chinese = "你好";
           HanyuPinyinOutputFormat format = new HanyuPinyinOutputFormat();
           format.setToneType(HanyuPinyinToneType.WITH_TONE_NUMBER);
           
           String pinyin = PinyinHelper.toHanyuPinyinString(chinese, format, " ");
           System.out.println(pinyin);  // Output: ni3 hao3
       }
   }